Internal-combustion engine



May 14, 1929- AQv. D. wlLLGoos INTERNAL COMBUSTION ENGINE Filed Dec. fr, 192e lll/11,111,000',

Patented May 14, 1929.

UNITED STATES PATENT OFFICE.

ANDREW V. D. WILLGOOS, 0F WEST HARTFORD, CONNECTICUT, ASSIGNOR TO THE PRATT & WHITNEY AIRCRAFT C0., OF HARTFORD, CONNECTICUT.

INTERNAL-COMBUSTION ENGINE.

Applicationilled December 7, 1926. Serial No. 153,165.

This invention relates in generalto internal combustion engines and more particularly to means for cooling and Ventilating the exhaust valves thereof.

This invention is more especially concerned with internal combustion engines of the air-cooled t pe in which considerable diflculty has been experienced in obtaining proper cooling for the exhaust valve and exhaust valve stems. i t

It is desirable to inclose the valve operating parts of an engine, to facilitate lubrication and to exclude dirt and water. However, when such inclosure is effected, Water and other corrosive substances form in the housing, in defeat of the purpose thereof. The source of these substances is the exhaust gas which leaks out between the stem and guide of the exhaust valve, and from which the aforementioned substances condense. My invention is directed to the ventilation of the valve stem in such a way as to lprevent the entrance of products of combustion to the valve mechanism inclosure.

It is an object of my invention to provide means for insuring adequate cooling -of the exhaust valve and stem without the addition of any structural parts to the en ine.

It is a further object of my lnvention to ventilate the exhaust valve stem so as to prevent access of exhaust gases to the valve operating parts.

Other objects of my invention will appear in the accompanying specification and claims and will be disclosed in the accompanying drawings in which- The figure is a central vertical Section through a cylinder embodying my invention.

Re erring now with greater particularity to the drawings it will be seen that my improvement is comprised as follows:

The combustion chamber 1 of a cylinder 2 is provided with suitable cooling fins 3 throughout its length and that of the valve stem guide or boss 4 which is formed integrally with the cylinder and constitutes an extension thereof. The cylinder extensionis also formed to provide achamber for the reception of the valve actuating mechanism including the upper end of the push rod 6', the rocker arm 7, and the valve springs 8. The chamber 5 is substantially closed to outside atmos here to prevent the ingress of moisture, dirt, etc. An inspection opening 5a isbprovided with a removable dust proof ca he boss 4, substantially centrally of its length, is provided with a bore 9, extending in a direction upstream of the relative air flow past the engine cylinder due, in the case of a moving engine, to the motion of the engine through the air, or, in case of a stationary engine, to a blast induced' by some other means. The bore 9 leads into an annular chamber 10 which is provided with an outlet bore l1, somewhat larger than the bore 9, aligned with the bore 9 and having its outlet into the exhaust manifold 12 and in a direction downstream of the flow of exhaust gases through said manifold.

valve stem guide 13 is mounted in the boss 4 and slidably supports the valve 14. The guide 13 is provided with bores 15 and 16 aligned with, and substantially proportional in size to the bores 9 and 11, respectively. The bores 15 and 16 serve as inlet and outlet means lfor the ventilation of an amular chamber 17 formed within the guide From the foregoing it will be seen that the flow of coolingair past the engine e linder will result in a flow of cooling air t rough the bores 9, 11, 15 and 16 providing a constant supply of cooling air to the chambers 10 and 17 and contacting directly with the valve stem and the walls of the valve stem guide. The flow of exhaust gases in the exhaust manifold augments by induction the ow of cooling gases around the valve guide and valve stem since the outlet of the bore 11 faces downstream of the said exhaust gas flow. Any exhaust gases, due to l leakage past 18 and 19, tending to pass into the chamber 5 around the valve stem or valve stern guide, are picked up in the chambers 10 and 17 and carried out into the exhaust manifold. My invention thus provides adequate cooling and Ventilating means for my exhaust valve.

Having thus described my invention what I claim is- 1. In combination, in an internal combustion engine, a cylinder, a valve mounted in,

a guide in said cylinder, an inlet aperture in said cylinder faced to meet the rush of air past the engine and communicating with an annular passageway around said guide, and an outlet for said cooling air diametrically opposed to said inlet.

2. In combination, in an internal combustion engine, a valve mounted in a guide in said engine, an inlet aperture faced to meet the rush of air pastthe engine and communicating with an annular passageway around said guide, and an outlet for said cooling air diametrically opposed to said inlet and opening into the exhaust manifold of said engine.

3. In combination, in anA internal combustion engine, a cylinder, a. valve mounted in a guide in said cylinder, an inlet aperture faced to meet the rush of air through which the engine passes and communicating with an annular passageway around said guide, and an outlet for said cooling air diametrically opposed to said inlet and opening into the exhaust manifold on said engine, which manifold extends parallel to and in the direct-ion of the fiow of gases from said inlet to said outlet.

4. In an internal combustion engine, a

cylinder, a valve, a valve stem mounted in a guide in said cylinder, an annular passageway in said guide around said stem and open to the air, and means operatively connecting said passageway with the exhaust port of the cylinder for inducing a flow of cooling air around said valve stem.

5. In an internal combustion engine, a cylinder, a valve, a valve stem mounted in a guide in said cylinder, an annular passageway in said guide around said stem and open to the air, and means operatively connecting said passageway with the exhaust port of the cylinder for inducing a flow of cooling air around said valve stcm in direct contact therewith.

6. In an` internal combustion engine, a cylinder, a valve, a valve stem mounted in a guide in said cylinder, an annular passageway around said stem,-an inlet to said passageway open to the air, and an outlet from said passageway opening into the exhaust manifold of said engine.

7. In an internal combustion engine, a cylinder, a valve, a valve stem mounted in a guide in said cylinder, an annular passageway in said guide around said stem, an inlet to said passageway open to the air, and an outlet from said passageway open to the exhaust manifold of said engine.

8. In an internal combustiony engine, a cylinder, a valve having its stem mounted in a guide in an integral 'extension of said cylinder, an annular chamber in said extenslon around said guide, an annular chamber in said guide around said stem, and means for conducting cooling air through said chambers.

9. In an internal combustion engine, a. cylinder, a valve having its stem mounted in a guide in an integral extension of said cylinder, an annular chamber' in said extension around said guide, an annular' chamber in said guide around said stem, and means open to the air for conducting cooling air to said chambers, and means open to thc exhaust manifold for exhausting said chambers.

In testimony whereof I aix my signature.

ANDREW V. D. WILLGOOS. 

